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meena.shah

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Hi! Can anyone please tell me how to infuse spirulina and indigo powder in the oil and how much and how long should I keep it for infuse.
 
First you are going to need tea bags or some very small micron bags to put those powders in. Using the tea bags will make it much easier when the infusion is done. If you can't get unused tea bags where you are or you don't want to use them, then you will need a coffee filter to run your infusion through when it is done because you don't want the leftover material in your final product.

Then you need to decide what oil you want to use in your infusion. Some good ones that I use are soybean, sunflower or hemp oil. Some ingredients infuse better in certain oils. Once you have the oil that you want to use, you will need a jar. I use pint size canning jars with new lids because I don't need a lot of the infusion and it will give you an air tight seal, which is important. but you can use what ever size you want. Then you need to decide what strength you want in your infusion. For fine powder like you have, I would use 1 tablespoon to 1 pint of oil.

Put the material in your tea bag, seal the tea bag and drop it in the oil. You may need to hold it in the oil for a few minutes, until it stops floating. Once that is done, seal the jar tightly and shake it. I would let it set for at least 24 hours. I let mine set for 30 days for a strong infusion and I shake it every few days.

The spirulina is a very fine powder and it may leak through the tea bag. So be prepared to filter out the finished infusion many times.
 
please tell me how to infuse spirulina and indigo powder in the oil and how much and how long should I keep it for infuse.
These two infusions have been discussed many times. In addition to @Todd Ziegler 's excellent advice above, you may also want to find the magnifying glass icon at the top right of this page and Search for "indigo" and "spirulina" for more information. ;)
 
I always think the word “infusion” is a bit confusing and also don’t find that I need to mix up big indigo and spirulina infusions to get the colors I want. You can infuse oil with pigment that will diffuse out of indigo or spirulina powder or you can use the powders that have been soaked/dispersed in oil, or you can use both. These days, I typically mix my indigo powder (1 unit, like a teaspoon) with liquid oil of choice (3x volume of indigo) and let it sit for at least a few hours and sometimes for a couple of days before I want to use it. I can achieve medium to dark shades of blue by slurrying the mix together before I spoon a bit of it into my emulsified batter. See the middle soap here as an example. I keep adding it until I get the shade I want. My batch sizes are usually 1000 g of oils, and I might end up using a teaspoon of indigo slurry for a medium shade. The strength of the indigo powder will make a difference, but it’s somewhat trial and error. Indigo tends to looks grey in batter, so I go by how dark the batter is getting rather than the actual color. I keep my superfat low to allow for the extra oil I’m adding. I‘ve done the same with spirulina, but not often. The indigo and spirulina I use are very fine and add no perceptible graininess to my soap (visual or in use).

ETA: I just checked my notes for the soap that’s pictured in my avatar photo. For that one, I used almost a teaspoon of powder mixed in a little batch oil plus about an 1/8th of a teaspoon of activated charcoal to get that deep shade of blue in a batch that was 550 g of oils. That’s more indigo powder ppo than I indicated above. For that soap powder I added the indigo slurry to the oils before adding the lye water because I knew I wanted a deep shade of blue.
 
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I've been wondering about indigo recently also - I've only ever worked with it for dying wool previously, and it's a whole rigmarole involving ammonia. Would any of the chemistry experts care to weigh in as to why it works in soap without all of that process? Does the lye somehow take the place of the ammonia so that all that is needed is to get the indigo powder into some kind of suspension for it to work in soap?
 
I always think the word “infusion” is a bit confusing and also don’t find that I need to mix up big indigo and spirulina infusions to get the colors I want.

ETA: I just checked my notes for the soap that’s pictured in my avatar photo. For that one, I used almost a teaspoon of powder mixed in a little batch oil plus about an 1/8th of a teaspoon of activated charcoal to get that deep shade of blue in a batch that was 550 g of oils. That’s more indigo powder ppo than I indicated above. For that soap powder I added the indigo slurry to the oils before adding the lye water because I knew I wanted a deep shade of blue.
Thank you so very much for sharing this info, @Mobjack Bay . I've been paralyzed with researching and wondering (especially about "infusing" and what seem to be so many different methods) what to do with my new found indigo - that wouldn't end up with me tearing up because I didn't know enough to not waste it. Soaping should NOT be stressful!!! LOL
 
This soap from July 2019, which was when I was making pint sized batches of oil with natural colorants, was colored with a combination of infused oils and slurried in oil powders. Moving up from the bottom, the first four layers were colored with infused olive oils where I used the infused oil at 20% of the recipe to mix little batches of soap. The yellow oil was from a jar with annatto powder, the green oil from a jar with matcha tea + some oil from a jar of spirulina. These would have been jars of 1 part powder mixed with 10 parts oil. The faded layer above the red was matcha-infused oil without spirulina infused oil. The red layer has madder powder added directly and it’s always been a bit scratchy. The dark green layer has spirulina powder added. The sky was colored with indigo and was light blue, but it has faded. The cloud has td. Note: the soap has been in use at my kitchen sink.

C7D9039F-1C35-457B-B17C-649A42AA74DC.jpeg

A takeaway for me from the testing I’ve done is that there are multiple ways to add colorants. Testing helped me determine what would work best with my recipes and methods. For spirulina and indigo powders, which are very fine/not scratchy, I mostly use slurries. For annato, I prefer to use a highly colored oil that I add to the batter. For madder, I find it easiest and get good results using a madder tea (filtered) to make the lye water.
 
Thank you so very much for sharing this info, @Mobjack Bay . I've been paralyzed with researching and wondering (especially about "infusing" and what seem to be so many different methods) what to do with my new found indigo - that wouldn't end up with me tearing up because I didn't know enough to not waste it. Soaping should NOT be stressful!!! LOL
I hope you give it a try. If you don’t want to do a lot of experimenting, try mixing 1/4 tsp powder with 3/4 tsp oil for a batch size of 300-500 g of oil. That should get you in the range if you’re using a natural indigo powder. If it’s the synthetic kind, it takes less based on my experience. There’s less risk of color fail if the soap is gelled and your base is close to white.
 
@kaygrrl The indigo that faded in the sky of the soap above was very pale to begin with. Here’s an end cut from the soap in my avatar photo (ETA: oops, no longer there). It has faded some, but not much. I intentionally forced “rivers” in this soap, which is what you can see happening above the bottom layer, so the bottom layer is the one to focus on. The soap was made in fall 2019. I move my natural color soaps into the dark as soon as I can, but indigo holds up relatively well in use, compared with Matcha tea colored soap which fades really fast.

2C67660F-AB9B-4A4B-84DC-4CAC034C4451.jpeg
 
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@kaygrrl The indigo that faded in the sky of the soap above was very pale to begin with. Here’s an end cut from the soap in my avatar photo. It has faded some, but not much. I intentionally forced “rivers” in this soap, which is what you can see happening above the bottom layer, so the bottom layer is the one to focus on. The soap was made in fall 2019. I move my natural color soaps into the dark as soon as I can, but indigo holds up relatively well in use, compared with Matcha tea colored soap which fades really fast.

View attachment 54726
Beautiful! And what a relief to know about Indigo holding up! How concentrated was your indigo infusion used here? I’m looking for something that’ll be sky blue but hold up hopefully too
 
Beautiful! And what a relief to know about Indigo holding up! How concentrated was your indigo infusion used here? I’m looking for something that’ll be sky blue but hold up hopefully too
The details for that soap are at the bottom of post #6. I used a slurry of indigo powder and oil as described. I recommend that you test indigo and methods before making a big batch of soap. The color intensity of indigo powder varies depending on the plant species (there are several), age of the plants harvested, and probably also depends on how the powder was processed. I bought my indigo powder here.
 
I've used alkanet infusion and didn't notice any smell at all. It also didn't work that well to create a deep color; maybe the feet odor is responsible for the lovely purple color?
 
I find that I use less indigo by infusing it than I do when making a slurry. But if your whole life s not governed by frugality (unlike mine) this might not be a concern for you. :rolleyes:

Also it really, really depends on where you buy your indigo. If you get it from dharma trading it is quite intense and you need less. If you buy it from other suppliers it can be really weak. So you really do have to test every batch of indigo you get and what works for someone else might not work for you. Then I find if you stick blend indigoed batter it gets darker than if I hand blend it. I also find soaping temperatures effect the indigo colour achieved. I find organic indigo a very very tempremental ingredient.

Instead of waiting for days for infusions to infuse I use a double boiler (or put a stainless steel bowl over a gently simmering saucepan of water) and keep it on really low heat for an hour or so. This speeds up the process considerably. I use this method for all infusions.

Pre reduced indigo (chemically synthesised indigo) is easier to work with.

This is a great blog on indigo.
https://www.greatcakessoapworks.com...how-to-use-indigo-to-color-cold-process-soap/
 
I've been wondering about indigo recently also - I've only ever worked with it for dying wool previously, and it's a whole rigmarole involving ammonia. Would any of the chemistry experts care to weigh in as to why it works in soap without all of that process? Does the lye somehow take the place of the ammonia so that all that is needed is to get the indigo powder into some kind of suspension for it to work in soap?
Sorry I don't know anything about the science.
You don't need ammonia to use indigo for clothes in this blog.
I've used this method to reduce my indigo and it certainly makes the indigo powder go further. We use tiny amounts of powered indigo to colour soap but you need to use a lot to colour fabric. That might be one reason people dying fabric bother to do it.
https://www.wearingwoad.com/creating-a-natural-indigo-dye-reduction-vat/
 
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